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1.
Genes for resistance to powdery mildew in European barley cultivars registered in the Czech Republic from 2011 to 2015 下载免费PDF全文
Antonín Dreiseitl 《Plant Breeding》2017,136(3):351-356
Barley (Hordeum vulgare) is cultivated on 49.1 million hectares worldwide with 50.2% of the area located in Europe. Powdery mildew, caused by Blumeria graminis f. sp. hordei (Bgh), occurs wherever barley is grown. Cultivar resistance plays an important role in global barley production, especially in parts of Europe where high concentrations of both spring and winter types are grown. The aim of this report was to postulate specific resistance genes in barleys from nine European countries registered in the Czech Republic from 2011 to 2015. Thirty‐five spring cultivars and 27 winter barleys were tested with 56 diverse Bgh isolates. Twenty‐five known resistance genes were postulated, and unknown genes were detected in Sandra, Saturn and Zeppelin. Unidentified specific resistance genes were also present in winter hybrids Hobbit and Wootan. Spring cultivars Arthur and Francin consisted of three and two genotypes, respectively. Resistance gene mlo was present in 26 spring cultivars, and the proportion of cultivars with this gene increased from 62.9% in 2006–2010 to 75.7% in 2011–2015. The gene Mlp1 was identified for the first time in German winter cultivar Saturn. Five spring cultivars registered in Slovakia were included in the tests. All the cultivars that were tested contained one or more specific resistance genes to powdery mildew. Adaptability of the pathogen and possibilities for breeding winter barleys are discussed. 相似文献
2.
The dispersal ecology of most stream fishes is poorly characterised, complicating conservation efforts for these species. We used microsatellite DNA marker data to characterise dispersal patterns and effective population size (Ne) for a population of Roanoke logperch Percina rex, an endangered darter (Percidae). Juveniles and candidate parents were sampled for 2 years at sites throughout the Roanoke River watershed. Dispersal was inferred via genetic assignment tests (ATs), pedigree reconstruction (PR) and estimation of lifetime dispersal distance under a genetic isolation‐by‐distance model. Estimates of Ne varied from 105 to 1218 individuals, depending on the estimation method. Based on PR, polygamy was frequent in parents of both sexes, with individuals spawning with an average of 2.4 mates. The sample contained 61 half‐sibling pairs, but only one parent–offspring pair and no full‐sib pairs, which limited our ability to discriminate natal dispersal of juveniles from breeding dispersal of their parents between spawning events. Nonetheless, all methods indicated extensive dispersal. The AT indicated unrestricted dispersal among sites ≤15 km apart, while siblings inferred by the PR were captured an average of 14 km and up to 55 km apart. Model‐based estimates of median lifetime dispersal distance (6–24 km, depending on assumptions) bracketed AT and PR estimates, indicating that widely dispersed individuals do, on average, contribute to gene flow. Extensive dispersal of P. rex suggests that darters and other small benthic stream fishes may be unexpectedly mobile. Monitoring and management activities for such populations should encompass entire watersheds to fully capture population dynamics. 相似文献
3.
旨在对广灵县优种驴场保种群体进行调查的基础上构建分子系谱,并对其种群的遗传结构进行分析。本研究采集保种群成年、体况良好的广灵驴(体重350~400 kg)颈静脉血10 mL(n=107),其中公驴13份,母驴94份,抗凝处理后提取全血DNA。采用12个微卫星标记进行荧光PCR扩增后,用ABI3730测序仪进行分型。分型结果采用Cervus 2.0和Pedigraph 2.4软件构建分子系谱,同时采用STRUCTURE2.3和Fstat软件计算群体遗传参数,采用R语言的hclust函数绘制7头公驴及其后代的系统发生NJ树(邻接树)。结果,对107头种驴进行了分子系谱构建,找到了30头子代的父亲和7头子代的母亲,系谱可靠性>90%;微卫星标记的平均观测杂合度(HObs)和多态信息含量(PIC)分别为0.676 5和0.593 9,标记遗传多样性较高;NJ树对7个公驴家系进行了聚类;群体分化系数(FST)为0.184,群体平均近交系数(FIT)为0.033,群体内近交系数(FIS)为-0.238,且群体处于哈代-温伯格平衡状态,存在很弱的近交。本研究建立了广灵驴保种群可靠性较高的分子系谱并对其遗传结构进行了分析,证明该群体遗传多态性较高,群体近交系数较低,处于较好的保种状态,具有较大的品种资源开发潜力。 相似文献
4.
Ryota Komiya Shinichiro Ogawa Tatsuya Aonuma Masahiro Satoh 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2022,139(1):113-124
Genome-wide single nucleotide polymorphism (SNP) markers in Japanese Black cattle enable genomic prediction and verifying parent–offspring relationships. We assessed the performance of opposing homozygotes (OH) for paternity testing in Japanese Black cattle, using SNP genotype information of 50 sires and 3,420 fattened animals, 1,945 of which were fathered by the 50 genotyped sires. The number of OH was counted for each sire–progeny pair in 28,764 SNPs with minor allele frequencies of ≥0.05 in this population. Across all pairs of animals, the number of OH tended to increase as the pedigree-based coefficient of relationship decreased. With a threshold of 288 (1% of SNPs) for paternity testing, most sire–progeny pairs were detected as true relationships. The frequency of Mendelian inconsistencies was 2.4%, reflecting the high accuracy of pedigree information in Japanese Black cattle population. The results indicate the utility of OH for paternity testing in Japanese Black cattle. 相似文献
5.
A cleaved amplified polymorphic sequence marker was used to detect the alleles Bmy‐Sd2H and Bmy‐Sd3 identifying highly thermostable isoforms of the enzyme b‐amylase, which improves fermentability during brewing. Among the 889 accessions of barley (Hordeum vulgare) investigated, and two accessions of H. spontaneum a total of 166 accessions were identified carrying the superior b‐amylase alleles. These thermostable alleles of b‐amylase were most frequently observed in six‐rowed varieties originating from Asia, especially Japan, with 61.9% of the accessions from Asia carrying the alleles of interest. Additional six‐rowed barleys carrying the relevant alleles were identified among accessions from America, Africa and the Near East. In the European varieties, the percentage of accessions with the alleles of interest was 5.1% with a strong predominance in two‐rowed spring barleys. A pedigree analysis identified the cross ‘Binder’ x ‘Gull’ as the main source of the thermostable b‐amylase alleles in European varieties. The data suggest that an improvement of malting quality in barley could be achieved by introduction of the Bmy1‐Sd2H and Bmy1‐Sd3 alleles into the European breeding programmes. 相似文献
6.
Summary Four populations of linseed derived from five parents were advanced from the F2 to the F6 generation by SSD and to the F5 by pedigree selection. These populations were used to compare the efficiency of the two methods in order to provide superior genotypes with respect to grain yield and oil content, i.e. oil yield. The results showed minimum differences between pedigree and SSD lines for grain yield, where in only one cross the SSD lines were significantly superior to the pedigree lines. Since pedigree selection was carried out for both, seed yield and oil content, a positive response to selection was expected. However, early selection for yield, a character with low heritability, was not successful. On the contrary, significant differences for oil content were detected between the two groups of lines in three of the four crosses studied. In these cases the pedigree lines were superior to the SSD lines. These results demonstrate that strict selection in early generations for oil content, a character with comparatively high heritability, is feasible and successful in linseed. However, selection for seed yield should be postponed to later inbred generations. Consequently, in breeding for maximum oil yield of linseed a two-step selection procedure is recommended.Abbreviations PS
pedigree selection
- SSD
single seed descent
- TGW
thousand grain weight 相似文献
7.
阐述了湖南优异地方辣椒品种资源‘伏地尖’的挖掘、评价及其衍生骨干亲本‘5901’的
选育过程和主要特征特性,并查阅相关文献资料,对利用‘5901’和衍生亲本选育的品种和推广应用进
行分析。结果显示,该地方品种和骨干亲本材料具极早熟、耐低温弱光、前期产量高、配合力及制种产
量高等特性。中国1988—2014 年直接或间接利用‘5901’选育并在全国大面积推广应用的辣椒品种共31
个。绘制了辣椒骨干亲本‘5901’系谱图,为辣椒骨干亲本的创制及利用提供参考。 相似文献
8.
Joseph H. Anderson George R. Pess Peter M. Kiffney Todd R. Bennett Paul L. Faulds William I. Atlas Thomas P. Quinn 《Ecology of Freshwater Fish》2013,22(1):30-42
Anadromous fishes are frequently restricted by artificial barriers to movement such as dams and culverts, so measuring dispersal helps identify sites where improved connectivity could promote range expansion and population viability. We used a combination of DNA‐based parentage analysis and mark–recapture techniques to evaluate dispersal by juvenile coho salmon (Oncorhynchus kisutch) in a population in the initial stages of colonisation following installation of fish passage structures at a previously impassable dam on the Cedar River, WA, USA. The spatial distribution of individuals within maternal families revealed that dispersal was common. Among the offspring of radio‐tagged mothers, 28% were collected outside the spawning reach and dispersed up to 6.3 km (median = 1.5 km). Most juveniles captured in a tributary (Rock Creek, where few adults spawned) had immigrated from the Cedar River and represented many different families. Juvenile dispersal therefore provided a secondary phase of spatial expansion following initial colonisation by adults. Consistent with the condition‐dependent dispersal hypothesis, juveniles that dispersed farther upstream in the tributary were larger than fish collected near the tributary mouth. Overall, the results demonstrated widespread dispersal in a system with low coho salmon densities, and this might increase the rate of population growth if it reduces the effects of local density dependence. By implication, juveniles can take advantage of rearing habitats reconnected through barrier removal, even when such areas are located several kilometres from adult breeding grounds. 相似文献
9.
10.
The establishment and evaluation of family lines using pedigree information provides an advanced understanding of the variability that exists for complex, economically valuable traits and is a necessary step in the execution of an effective breeding programme. The aim of this study was to assign parentage to mass‐spawned Haliotis midae juveniles using species‐specific microsatellite markers. Screening of wild abalone individuals revealed that the nine loci selected complied with the minimum requirements for parentage analyses: a null allele frequency <5% as well as a high number and frequency of alleles per locus. A total of 598 individuals were genotyped (198 breeding individuals and 400 F1 progeny) from two farms, with parentage results yielding 91% and 90% successful assignment for Farms A and B respectively. This study, therefore, provided the necessary pedigree information required for controlled breeding of individual adult abalone and indicated the usefulness of the panel of microsatellite markers selected for parentage assignment. 相似文献